google-nomulus/javatests/google/registry/testing/SystemInfo.java
Michael Muller c458c05801 Rename Java packages to use the .google TLD
The dark lord Gosling designed the Java package naming system so that
ownership flows from the DNS system. Since we own the domain name
registry.google, it seems only appropriate that we should use
google.registry as our package name.
2016-05-13 20:04:42 -04:00

64 lines
2.3 KiB
Java

// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package google.registry.testing;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import google.registry.util.FormattingLogger;
import java.io.IOException;
import java.util.concurrent.ExecutionException;
import javax.annotation.concurrent.ThreadSafe;
/** Utility class for getting system information in tests. */
@ThreadSafe
public final class SystemInfo {
private static final FormattingLogger logger = FormattingLogger.getLoggerForCallerClass();
private static final LoadingCache<String, Boolean> hasCommandCache = CacheBuilder.newBuilder()
.build(new CacheLoader<String, Boolean>() {
@Override
public Boolean load(String cmd) throws InterruptedException {
try {
Process pid = Runtime.getRuntime().exec(cmd);
pid.getOutputStream().close();
pid.waitFor();
} catch (IOException e) {
logger.warningfmt(e, "%s command not available", cmd);
return false;
}
return true;
}});
/**
* Returns {@code true} if system command can be run from path.
*
* <p><b>Warning:</b> The command is actually run! So there could be side-effects. You might
* need to specify a version flag or something. Return code is ignored.
*
* <p>This result is a memoized. If multiple therads try to get the same result at once, the
* heavy lifting will only be performed by the first thread and the rest will wait.
*
* @throws ExecutionException
*/
public static boolean hasCommand(String cmd) throws ExecutionException {
return hasCommandCache.get(cmd);
}
}